Extraction of Moringa oleifera Leaves to Obtain Antioxidants and Vitamins

Moringa leaves have become popular as a dietary supplement and herbal medicine. Therefore, it would be of nutritional benefit to determine the appropriate extraction method and solvent that would promote the extraction with high biological activity and high yield of active compounds to produce nutraceuticals. In this study, an evaluation of two methods of extracting bioactive compounds from Moringa oleifera leaves was proposed. In this evaluation, some parameters were compared, such as the yield, the content of extracted phenolic compounds, the antioxidant activity and the quantity of vitamins extracted and preserved in the extracts. Three types of solvents: water, ethanol (EtOH) and ethyl acetate (Act) were used at two different temperatures and different extraction times. The average extraction yield in the hot bath shows an increase of 13.2% when compared to vacuum pressure bath extraction. In terms of phenolic compound content and antioxidant activity, the average increase was 4.9% and 4.3%, respectively. Vitamins were detected in the samples and, due to their polarity, they were mostly found in the solvent with the presence of ethanol (50% and 100% of EtOH). The solvent with the presence of ethyl acetate (50% and 100% of Act) showed low yield and low solubility with the compounds of interest in the extractions, such as phenolic compounds and vitamins. The positive effect of low pressure on the extraction of fat-soluble vitamins was observed.